Or, rather, a fire exhaling animal.
Couple of things to ponder…
Which chemicals when mixed together (or when they come into contact with air) will combust?
Are any of these chemicals readily available in the animal kingdom? (are any of these chemicals produced in some manner by animals/insects)
For example; viper venom and stink beetle juice. Let’s say that the two chemicals combusted. We could then start to dream up ways in which scientists could cross breed the two to conjur up a fire-breathing creature.
So, how far fetched is the idea of a fire-breathing animal?
Lots of animals produce methane. Even mammals, if you’re interested in a fire-farting species.
Therefore, the only remaining challenge is coming up with an ignition source. But if eels can generate voltage, the ability to manipulate electricity isn’t impossible in the animal kingdom. So work that into a sparking ignition source, spew some accumulated methane across it, and presto!
I read an article in Omni a long time ago that opined that dragons could generate a surplus of hydrogen in their guts and belch it out, igniting it by… I don’t remember. Something about making a spark by biting down on a rock, I think.
It’s pretty difficult for me to imagine circumstances which would allow a creature to develop the anility to manufacture and store quantities of flammable substance, propject it, and ignite it. This is a couple of orders of magnitude more difficult , I think, than a bombadier beetle’s capability.
even if you could imagine the storage ability developing first for some entirely different reason (the way a sperm whale’s head is filled with oil, whichj is now believed IIRC as a sort of sonar “lens”), you’d think that the high mortality rate due to acidents involving that substance would prevent further evolution. (Bombadier beetle’s toxic output are created as they are expelled by the mixing of components. – I can’t think of an analogue that’s highly flammable).
There was a book by, um, I forget the author but I think it’s called The Flight of Dragons. It’s all about how a real “dragon” could exist, anatomically and whatever. I read it more than a decade ago, I think, but I remember he ended up posing a Chinese body type, and it flew and breathed fire with hydrogen. It’s been ages since I read it, though.
I can (well, in a vague, general sense) - an on-demand mixture of hydrogen peroxide and some kind of fairly volatile organic doesn’t seem all that far-fetched or implausible, or how about a dispersed cloud of flammable powder (not sure how ignition could be managed here).
There was an animated TV special (by Rankin-Bass, no less) called “A Flight of Dragons” that drew on two works – Peter Dickinson’s “The Flight of Dragons” and Gordon R. Dickson’s “The Dragon and the George”. I’ve only read the latter (and seen the cartoon, which gave us a pre-Clifford John Ritter as a dragon and Harry Morgan as a wizard) , but the pseudoscientific recipe for dragon’s breath wasn’t terrifically convincing. (And I don’t think it was meant to be) Mangetout – my my chemistry expertise runs out here. I know that the alkali metal peroxides (sodium peroxide, etc.) are powerful flaming agents, but I never heard that Hydrogen peroxide was (although it is high reactive, and IIRC is involved in the bombadier beetle’s defense).
My own qualification in the field of chemistry is of the armchair variety, so I might be completely wrong, but I know that hydrogen peroxide is used as an oxidant in rockets, with the other chemical often being something like kerosine.
So I would suggest that an animal capable of synthesising a fairly concentrated oxidant (like H[sub]2[/sub]O[sub]2[/sub]), and a fairly readily-oxidised organic compound (say, similar to linseed oil), and propelling these simultaneously as aerosolised clouds (to mix in the air after expulsion) could, to all intents and purposes, breathe fire. It’s not all that likely, but not entirely impossible, I’m sure.
A higher percentage of atmospheric oxygen (as has been hypothesised to exist in Earth’s history) would also help, I’m sure.
There are rocket fuel combinations that don’t require an ignition source; all you need is a couple of valves to control mixture. They are called hypergolic fuels. However I doubt if anything on that list can be made inside an animal’s body.
I’d also imagine that if you manage to evolve the ability to produce just one of the chemicals (not the combination of two), it’d be reactive enough that it can be used for defense without the need for combustion.
Did a quick lookup on Hydrogen peroxide and bombadier beetles:
1.) Merck Index says 90% h2o2 is used in rocket propulsion, and that h202 can explode in the presence of organic impurities.
2.) Wikipedia on Bombadier beetles confirms that it uses H202 and another substance, but that there’s no reaction in the absense of a catalyst (! who’d a thunk?)
3.) All very educational, and now I need to know more. But, judging from the above, I’ll bet the BB uses a dilute solution of H202, which is probably not good for sustaining flames, and 90% H202 isn’t recommended for anything organic to use. Any hypothetical dragons would need pretty well constructed storage and reaction chambers.
I haven’t got the time to look it up now, but the “swamp gas” some suggested might be responsible for OFOs (also called “will o’the wisp” and other nanmes) is a naturally occurring gas that spontaneously ignites on contact with moist air (it’s not methane, but I can’t now recall the composition). It is, I suppose, one candidate for this discussion. Since the stuff lityerally does come from swamps, you’d need some kind of fermentation vat to gebnerate it – more of a dragon-cow than a stately dragon. And I’m not sure you’d get much 'loft" from a dflamethrower made of this stuff.
All well and good, but there are many, many examples in nature of creatures evolving highly unlikely behaviors and traits. Once such example is typing this post (and presumably another is reading it ;))
Fun as the book was, IIRC, she used nuclear fusion[!] as the fuel source. Evolutionarily dicey.
The problem I don’t see discussed in this thread is the need to make the throat and mouth fireproof and yet usable as a eating/breathing pathway. Nature has come up with all sorts of dual purpose organs but this is a tough one to work through.
This isn’t too different from how Anne McCaffrey’s Pernese dragons do it - they chew up and swallow a particular kind of rock which when acted upon by stomach acids yields a phosphine gas that ignites spontaneously on being belched into the air.
It’d be a rather neat ability. I think calling it anile is harsh.
